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dan5505
11-17-2007, 02:58 PM
I hope this isn't a massive repost. I did a search and didn't come up with much. Does anyone have a generic answer to this?

rollerdj
11-17-2007, 03:03 PM
depending on what type / size of sub, what u are wanting to do with it, and the type of wood you are using, then yes. so the question is, what are u planning on doing?

dan5505
11-17-2007, 03:05 PM
Im planning to port a 15" Fi Q to 32 Hz with 3.5 cubes. http://www.subwoofertools.com/forum/ported-box.asp?Ew=36&Eh=18&Dia=9&Xmax=27&Vd=.19&NumW=1&Vb=3.5&Fb=32&Qts=&Vas=&Fs=&CE=0

rollerdj
11-17-2007, 03:08 PM
if u use some good 3/4" mdf i don't think u'll have to much of a problem. then again. the one i did that was allmost that size didn't give me any problems.

dan5505
11-17-2007, 03:40 PM
ok, cool. What sort of problems could arise? I'm guessin that the material could flex under stress causing a change in volume?

rollerdj
11-17-2007, 03:43 PM
that, could weaken the joints if not put together right. the one thing i would suggest is doing a double baffle so the screws for the sub won't break loss. if you are going for shear SPL or some kinda bass race, then u might wanna add a little. but for daily, u'll never know a differnce.

dan5505
11-17-2007, 04:09 PM
by double baffle, do you mean a double layer of mdf? Here is how far i am on the design so far.http://i159.photobucket.com/albums/t124/dan5505/ported15infiq.jpg
http://i159.photobucket.com/albums/t124/dan5505/ported15infiqopentop2.jpg
http://i159.photobucket.com/albums/t124/dan5505/ported15infiqopentop.jpg

Punk In Drublic
11-17-2007, 04:32 PM
I don't think you'll need that much port area but I'm not certain.. someone?

rollerdj
11-17-2007, 04:35 PM
don't know about the port area as there is no measurements there. a double baffle is IMO eather 2 sheets of mdf up front were ther sub is, or a extra ring around the cut out for the sub is so that the screws go though 2 layers instead of 1.

dan5505
11-17-2007, 04:40 PM
Sorry about the dimensions, most of them should be on this page:
http://www.subwoofertools.com/forum/ported-box.asp?Ew=36&Eh=18&Dia=9&Xmax=27&Vd=.19&NumW=1&Vb=3.5&Fb=32&Qts=&Vas=&Fs=&CE=0

I was guna put it into winisd and see what happened. so far this whole thing is based off of that link.

rollerdj
11-17-2007, 04:43 PM
at 32 sould do fine. like i said, i would double baffle it. anything over 12" IMO (unless a really beefy sub) should get double baffled.

rollerdj
11-17-2007, 04:43 PM
are u gonna build it or have someone else do it for u?

dan5505
11-17-2007, 04:45 PM
ohh no, ill definitely build it myself. Ill do the double baffle also. thanks for that idea.

rollerdj
11-17-2007, 04:46 PM
welcome. lets see some pics afterward too. :D

IgnoreMe
11-17-2007, 04:49 PM
you wont need any bracing for that box bro.

cool thing about slot port boxes (versus aero ports) is that the port (if long enough, like in your picture) acts as a brace. no need for a double baffle on that box either

rollerdj
11-17-2007, 04:50 PM
you wont need any bracing for that box bro.

cool thing about slot port boxes (versus aero ports) is that the port (if long enough, like in your picture) acts as a brace. no need for a double baffle on that box either

thats what i was thinkin after seeing the pic. lotta wood in there.

IgnoreMe
11-17-2007, 04:52 PM
thats what i was thinkin after seeing the pic. lotta wood in there.

for sure.

also you can do the double baffle if you wish, however lots of people will agree wooden dowels cross bracing inside the box are more effective.

and on top of everything else the Q isnt a very heavy driver. 1 baffle should suffice. you can double up if you want more bite with the screws, or you can just buy some hurricane nuts from parts express

rollerdj
11-17-2007, 04:53 PM
never seen a Q, whats the weight of one?

IgnoreMe
11-17-2007, 04:55 PM
never seen a Q, whats the weight of one?

i think they are in the low 30's. my 18" bl's were about 39lbs

rollerdj
11-17-2007, 05:00 PM
thats still some decint weight. allthough i know there is heavyer.

IgnoreMe
11-17-2007, 05:34 PM
thats still some decint weight. allthough i know there is heavyer.

my buddy got away with single baffle, sub back port back in his explorer, with an 05 15" xxx. 70lbs right there. single baffle, and nothing but wood screws. worked for 2 years before he finally sold the sub.

i wouldnt do a single baffle for an xxx with only wood screws (in fact i would highly advise against it), but it can be done. was tuned to 29hz, so the port was pretty long, and braced the box very well.

azbass
11-17-2007, 05:36 PM
imo, you should brace every enclosure you build. no matter how big or small. etc.

Mr Cabinetry
11-17-2007, 06:50 PM
imo, you should brace every enclosure you build. no matter how big or small. etc.

Well, then, all you would be doing is wasting time and material, not to mention adding displacement to an enclosure if your fighting for every cu.ft. of space you can get.

Not every sub enclosure needs bracing and I wouldn't waste my time with bracing one depending on the design for size of the enclosure and the subwoofer being used depending on how many watts the sub was being driven with.